Diabetes is a disease that, along with its precursor, prediabetes, is estimated to affect nine million Canadians. Diabetes is a disorder in which disease sufferers have problems processing glucose, a type of sugar, within the body which leads to increased levels of glucose in the blood. The increased levels of blood glucose can have negative effects on different organs within the body, including the eyes. There are different types of diabetes which include type 1 diabetes, type 2 diabetes, gestational diabetes and prediabetes:
— Type 1 diabetes occurs when individuals do not produce insulin, which is the protein that helps to process glucose within the body.
— Type 2 diabetes occurs when an individual’s organs do not use the body’s insulin efficiently or when the levels of insulin produced by the body are decreased; both scenarios lead to increased blood sugar levels in the body.
— Gestational diabetes occurs when diabetes temporarily occurs during pregnancy.
— Prediabetes is classified as having blood sugar levels that are higher than normal, but, not yet high enough to establish a diabetes diagnosis.
All forms of diabetes can have effects on eye health and it is recommended that people with diabetes have routine, yearly eye exams performed by a Doctor of Optometry to provide early detection and, if needed, early treatment of the eye problems associated with diabetes.
Vision can become temporarily blurry in people who have diabetes if the blood sugar levels are higher than they should be or if the blood sugar levels have large fluctuations throughout the day. Ultimately, if the blood sugar levels are outside of a normal range (as suggested by a general practitioner), the higher blood sugar levels actually effect the natural lens inside the eye, causing it to change shape which can slightly alter the glasses prescription. This is a temporary effect and the lens does return to its normal state once blood sugar levels are restored to normal. This is the reason why Doctors of Optometry often ask diabetics about their blood sugar levels before checking the glasses prescription. Optometrists may even delay a new glasses prescription if they believe the change may be due to a diabetic’s blood sugar levels.
The leaky blood vessels at the back of the eye can also lead to a condition where clear fluid (not blood or lipids) can leak into the macula or, the centre of clear vision, causing the macula to become swollen. The swollen retina produces a temporary vision loss that results in distorted and cloudy vision. If treated soon enough, this condition does not have to lead to permanent vision loss; timely intervention is the key to restoring vision for people with this condition known as diabetic macular edema.
Diabetes can have negative and sometimes permanent effects on vision. Many of the effects of increased blood sugars on the eye can be avoided with early detection, routine monitoring and appropriate treatment by an eye care professional. Regular diabetic screening and eye examinations by a Doctor of Optometry can help to maintain good eye health for people with diabetes.